The mom was behind the wheel of a rented Hyundai Elantra when she and her son got into an argument and he insisted he be allowed to drive, Capt. John Zotollo Jr. said.
The mother "noticed the son had a pocket knife (and) became frightened," Zotollo said.
She then "immediately exited the vehicle and called 911," he said. "The son then drove away."
Lt. Leigh Cadigan and Officers Adam Georgaros, Peter Romero and Marcos Torres took the boy into custody and recovered the vehicle about two hours later, the captain said.
They signed a delinquency complaint charging the boy with carjacking that will be heard behind closed doors in the Family Part of Superior Court in Hackensack.
"Officers contacted several agencies to assist with the well-being of the son, and the family situation in general," Zotollo said. "The Saddle Brook Police Department will continue to assist in this regard.
"The immediate action of our Patrol Officers and the efficiency of the preliminary investigation conducted enabled the juvenile and vehicle to be located safely and in a relatively short period of time," he added.
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